OT Safety on portable equipment

How about adding something from Meltric's switch rated series?
http://www.meltric.com/?gclid=COOhxc3OvqUCFcbc4AodiH6pYw

We have a few machines from Europe that don't have disconnects on them, and use plugs. We have multiple "hot sticks" located around the shop that let you shut off bus tap disconnects from the ground without having to use a ladder. Also, any dropped power cords we make sure to keep about 7 feet off the floor so you can walk under them but not have to use a ladder to reach to plug/unplug.

I can't quote you the article, but my boss (master electrician I'm apprenticing under) always told me you are not supposed to disconnect a plug under power. So all the equipment we build have has a disconnect on it we can shut off before unplugging it.

Is you question about "cord-and-plug-connected equipment" as a disconnecting means? hint do a google search on the quoted text.

Think about a corded power tool. I don't like the idea of just using a plug even a twist-lock. I have seen this alot in XP location where a disconnect will cost an extra $1,000. Instead they put a XP rated plug and socket connection for $400.
You may want to look up the old line of sight for disconnects and see what is says now. I think there was a revision on it. I don't have the books in the house with me. I design a disconnect means at line of sight same level with out ladders, platforms, etc.

Jeff do you have any of those panel PC any more?

If you don't like the plug as a disconnect, and I agree with Jeff, a twist lock is not a disconnect, and is not rated for breaking under load, although the meltric ones I posted are as they hide the arc inside the plug. For 240V 3ph would it not be easier and cheaper to buy a small 3 phase breaker panel and connect anything within sight to it? Use the breakers as the disconnect means and just pigtail plugs out from it?

NEC says handle on disconnect means cannot be more than six feet from floor.
EXCEPT overhead bus work - in this case NEC requires a pull stick.

Cord with plug is an allowable DISCONNECT means per NEC
BUT that does not make it safe or acceptible as ON OFF control.

I suppose six foot rule gets a little sticky with a plug at seven feet above floor but it beats bashing your brains out on em.

3 phase relocatable equipment will always pose a rotation problme. Seen lots of outfits fight it. Best solution I have found is have the MASTER phase rotation setup in shop - assemble equipment there - test it there and you should be OK. Use a rotation tester referanced to the shop for testing out in the field.

Dan Bentler

Thanks for the interest guys,

Christoff84, We do use those Meltric plugs on some of the
larger (200 amp) equipment. Maybe we should get a quote
on some for these smaller (50 amp) installations.


These grinders are supposed to be "off" when disconnecting
or connecting. Plugs are only for disconnecting means for
maintenance or service. All have contactors, primarily
for the safety circuits.

I sent a link of this thread to our safety director.

Jeff, I do have more of the panel pc's

I don't remember what those panels are I just rememeber you had some. Call me sometime

Jeff,

Get a copy of NFPA 70e for your personal and for the company's liability protection. If there is an incident, OSHA does not not accept ignorance as an excuse and your life or fellow employee's health are even more important. There are a lot of rules that you may not be aware of. I have a publication authored by Stallcup's and they explain the rules more at a sparkies level so you don't have to try to interpret code verbage.

Definitely a violation of some NEC requirements. I would review:

2008 NEC Article 240 Covers Overcurrent Protection and 240.24(A) Accessability: Disconnect means must be no higher than 79" from floor to top of disconnect. (Not sure if this directly applies)

Article 400 Covers Flex Cord, 400.7 covers Uses Permitted (B) Attachment Plugs has an exception for 368.56 and in 368.56(B)(2) "length ... shall not exceed 6 feet" which also has an exception requiring tension take-up devices, the cord should just not dangle from an overhead receptical.

Meltric may be a good option, check for the suitability as a disconnect under load for an inductive load, just because you can, does that make that the best way to address disconnecting while under load? Arcing usually causes metal to melt.